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How to initialize a private static const map in C++?
...ap>
using namespace std;
struct A{
static map<int,int> create_map()
{
map<int,int> m;
m[1] = 2;
m[3] = 4;
m[5] = 6;
return m;
}
static const map<int,int> myMap;
};
const map<int,int> A:: myMap = ...
How to throw an exception in C?
...m Wikipedia
#include <stdio.h>
#include <setjmp.h>
static jmp_buf buf;
void second(void) {
printf("second\n"); // prints
longjmp(buf,1); // jumps back to where setjmp
// was called - making setjmp now return 1
}
void firs...
How to implement a queue with three stacks?
...s of you good ideas.
EDIT: Explanation example:
| | | |3| | | |
| | | |_| | | |
| | |_____| | |
| | | |
| | |2| | |
| | |_| | |
| |_________| |
| |
| |1| |
| |_| |
|_____________|
I tried here with a little ASCII-art to show Stack1.
Every ...
How do I perform the SQL Join equivalent in MongoDB?
...ttps://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <field from the input documents>,
foreignField: <field from the documents of the "from" collection>...
How do I print the elements of a C++ vector in GDB?
...td::vector<int> called myVector, do the following:
print *(myVector._M_impl._M_start)@myVector.size()
To print only the first N elements, do:
print *(myVector._M_impl._M_start)@N
Explanation
This is probably heavily dependent on your compiler version, but for GCC 4.1.2, the pointer to t...
What is the difference between join and merge in Pandas?
...andas as pd
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key')
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key')
left.join(right, lsuffix='_l', rsuffix='_r')
val_l val_r
key
foo 1 4
bar 2 5
The same functi...
How to check if a python module exists without importing it
...mport can find something in python2, using imp
import imp
try:
imp.find_module('eggs')
found = True
except ImportError:
found = False
To find dotted imports, you need to do more:
import imp
try:
spam_info = imp.find_module('spam')
spam = imp.load_module('spam', *spam_info)
i...
What's the difference between dynamic (C# 4) and var?
... {
[CompilerGenerated]
private static class <Main>o__SiteContainer0
{
public static CallSite<Action<CallSite, object>> <>p__Site1;
}
private static void Main(string[] args)
{
Junk a = new Junk(); /...
Is there a foreach loop in Go?
...
https://golang.org/ref/spec#For_range
A "for" statement with a "range" clause iterates through all entries
of an array, slice, string or map, or values received on a channel.
For each entry it assigns iteration values to corresponding iteration
v...
What is a singleton in C#?
...Prevent outside instantiation
}
private static readonly Singleton _singleton = new Singleton();
public static Singleton GetSingleton()
{
return _singleton;
}
}
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